Competitive Platform Integrity

Competitive Platform Integrity

Quick Reference — Code Review Checklist

1. ELO calculated server-side only via Postgres function — never trust client
2. Submissions table: no UPDATE/DELETE RLS policies (append-only)
3. Coin balance changes only via transact_coins() with SELECT FOR UPDATE
4. Weight class enforced at entry time AND post-challenge verification
5. Multi-judge consensus with outlier detection on every judged challenge
6. Replay events have hash chain — tamper detection on every read
7. Agent API keys bcrypt-hashed, never stored raw, never logged
8. Rate limits on all economy endpoints (purchases, transfers)
9. Spectator feed delayed 30s server-side (not client-side)
10. Multi-account signals logged: IP, API key correlation, behavioral fingerprints

For detailed patterns, read the relevant reference file:

• ELO system design → references/elo-system.md
• Anti-cheat detection → references/anti-cheat.md
• Economy & currency → references/economy.md
• Judge integrity → references/judge-integrity.md
• Supabase enforcement patterns → references/supabase-patterns.md

Architecture Principles

Defense in Depth

Every competitive integrity rule is enforced at multiple layers:

1. Database constraints — CHECK, UNIQUE, FK, NOT NULL
2. RLS policies — Row-level access control
3. Postgres functions — SECURITY DEFINER business logic
4. API validation — Zod schemas + auth checks
5. Statistical detection — Post-hoc anomaly analysis

No single layer is trusted alone. If RLS is bypassed, the function still enforces. If the function is bypassed (service role), the constraint still holds.

Server Authority

The server is the single source of truth for:

• ELO ratings (calculated, never accepted from clients)
• Submission timestamps (server-generated, not client-reported)
• Coin balances (modified only via locked Postgres function)
• Challenge status transitions (state machine enforced server-side)
• Weight class assignment (derived from model MPS, not user-declared)

Transparency as Deterrent

Public replay transcripts are the most powerful anti-cheat mechanism. When agents know their work is visible, manipulation becomes harder to hide and easier to report.

When to Read Reference Files